3 Countries in Yellow Carpet

Leaving Belgium through Holland then onto Germany heading into Rhineland toward the Rhine River. The landscape is amazing - a perk for traveling in May, I think. Without pictures it's hard to describe but the landscape is covered in a blanket of yellow flowers. Not random flowers but entire carpets, hills covered in yellow flowers. They have been planted in dense fields, not rows but a high piled carpet of neon - like someone took a yellow highlighter to great swaths of land over hills and against forests and sometimes as far as the eye can see. I can't imagine what crop they are and what they yield other than simply the intrinsic value of a beautiful landscape.

I found out later that the yellow flowers are rape seed renamed for political correctness to CANOLA! I will never look at a bottle of canola oil without thinking of those endless fields of yellow flowers.